A global reference data set for land cover mapping at 10 m resolution

Abstract. This paper presents a unique global reference data set for land cover mapping at a 10 m resolution, aligned with Sentinel-2 imagery for the year 2015. It contains more than 16.5 million data records at a 10 m resolution (or 165 K data records at 100 m) and information on 12 different land cover classes. The data set was collected by a group of experts through visual interpretation of very high resolution imagery (e.g., from Google Maps, Microsoft Bing, ESRI World), along with other sources of information provided in the Geo-Wiki platform (e.g., Normalized Difference Vegetation Index time series, Sentinel-2 image time series, geo-tagged photographs, and street view imagery). To ensure high quality and consistency among the experts that collected the data, regular coordination meetings took place, there were regular quality checks of expert submissions, and comparison with regional land cover maps was undertaken. This extensive reference land cover data set can be used in various applications, e.g., land cover analysis, including mapping and quality verification, ecosystems mapping and modelling, and biodiversity and cropland studies, among others. The data set is available for download at https://zenodo.org/records/14871660.